Methods and apparatus for assembling gas turbine engines

Abstract

A method is provided for operating a gas turbine engine including a core engine having a core stream duct, an inner bypass duct, an outer bypass duct, and a nozzle assembly downstream of the core engine and including a core engine nozzle and a bypass nozzle separated by a liner. The method includes channeling a first airflow discharged from the core gas turbine engine to the core engine nozzle, and channeling a second airflow through the inner bypass duct such that the second airflow bypasses the core gas turbine engine. The second airflow is channeled to a plurality of fairings that are positioned upstream from a plurality of support struts coupled to the nozzle assembly liner. The method also includes channeling a third airflow through the outer bypass duct such that the third airflow bypasses the core gas turbine engine, wherein the third airflow is channeled through the support struts to the bypass nozzle.

1. A method for operating a gas turbine engine including a core engine having a core stream duct, at least one bypass duct, and a nozzle assembly downstream of the core engine and including a core engine nozzle and a bypass nozzle separated by a liner, said method comprising:
 channeling a first airflow discharged from the core gas turbine engine to the core engine nozzle; and 
 channeling a second airflow through the at least one bypass duct such that the second airflow bypasses the core gas turbine engine, wherein the second airflow is channeled through a plurality slots defined at a downstream end of a plurality of fairings, wherein the plurality of fairings are upstream from a plurality of support struts coupled to the nozzle assembly liner, such that at least a portion of the second airflow is mixed with the first airflow. 
 
   
   
     2. A method in accordance with  claim 1  wherein the gas turbine engine includes an inner bypass duct and an outer bypass duct, said channeling a second airflow comprises channeling a second airflow through the inner bypass duct, and said method further comprises channeling a third airflow through the outer bypass duct such that the third airflow bypasses the core gas turbine engine, wherein the third airflow is channeled through the support struts to the bypass nozzle. 
   
   
     3. A method in accordance with  claim 1  further comprising channeling at least a portion of the second airflow to the bypass exhaust nozzle through the fairings. 
   
   
     4. A method in accordance with  claim 1  further comprising:
 channeling at least a portion of the second airflow channeled to the plurality of fairings to the support struts; and 
 controlling an amount of airflow channeled to the support struts using a valving system. 
 
   
   
     5. A method in accordance with  claim 1  wherein the bypass nozzle is in flow communication with the fairing, said method further comprising:
 channeling at least a portion of the second airflow channeled to the plurality of fairings to the support struts; and 
 controlling an amount of the second airflow channeled to the support struts by controlling an amount of airflow channeled through the bypass nozzle. 
 
   
   
     6. A method in accordance with  claim 1  further comprising controlling an amount of the second airflow mixed with the first airflow using a valve positioned between the plurality of fairings and the plurality of support struts. 
   
   
     7. A method in accordance with  claim 1  wherein said channeling a second airflow further comprises channeling the second airflow along an outer surface of the support struts to facilitate film cooling the outer surface of each of the support struts. 
   
   
     8. A nozzle assembly for an engine including a core engine and at least one core engine bypass duct for channeling airflow around the core engine, said nozzle assembly comprising:
 a liner comprising an inner surface and an outer surface, said inner surface confining airflow within a nozzle bypass duct, said outer surface confining airflow discharged from the core engine; 
 a plurality of strut members coupled to and supporting said liner; 
 a plurality of fairings in flow communication with the at least one core engine bypass duct, each said fairing upstream from a respective one of said plurality of strut members to facilitate directing a portion of the airflow from at least one core engine bypass duct towards said plurality of strut members through a plurality of slots defined at a downstream end of said plurality of fairings. 
 
   
   
     9. A nozzle assembly in accordance with  claim 8  wherein the at least one core engine bypass duct includes an inner bypass duct and an outer bypass duct, the inner bypass duct in flow communication with said fairing, the outer bypass duct in flow communication with said strut, each of said fairing and said strut in flow communication with said nozzle bypass duct, wherein at least a portion of the airflow from each of the inner and outer bypass ducts is exhausted from said nozzle bypass duct. 
   
   
     10. A nozzle assembly in accordance with  claim 8  wherein said nozzle assembly further comprises a core nozzle exhaust and a bypass nozzle exhaust, said liner defining each of said core and bypass nozzle exhausts. 
   
   
     11. A nozzle assembly in accordance with  claim 8  wherein the portion of the airflow directed from the core engine bypass duct towards said plurality of strut members by said plurality of fairings is controlled by varying a throat area of one of a core exhausts and a nozzle exhaust. 
   
   
     12. A nozzle assembly in accordance with  claim 8  wherein each of said plurality of fairings comprises a valve positioned between said plurality of fairings and said plurality of strut members, said valve facilitates controlling an amount of airflow channeled toward said plurality of strut members. 
   
   
     13. A nozzle assembly in accordance with  claim 8  wherein the portion of the airflow directed from the core engine bypass duct past said plurality of strut members by said plurality of fairings is mixed with the airflow discharged from the core engine. 
   
   
     14. A gas turbine engine assembly comprising:
 a core gas turbine engine comprising a core engine airflow stream; 
 at least one core engine bypass duct channeling a bypass airflow stream therethrough; and 
 a nozzle assembly downstream of said core engine and said at least one core engine bypass duct, said nozzle assembly comprising a liner separating airflow discharged from said core engine from airflow within a nozzle bypass duct, a plurality of strut members coupled to and supporting said liner, and a plurality of fairings in flow communication with said at least one core engine bypass duct, each of said plurality of fairings positioned upstream from a respective one of said plurality of strut members and channeling a portion of airflow from said core engine bypass duct towards said plurality of strut members through a plurality of slots defined at a downstream end of said plurality of fairings. 
 
   
   
     15. A gas turbine engine assembly in accordance with  claim 14  wherein a portion of the bypass airflow stream is mixed with the core engine stream discharged from the core engine upstream of said nozzle assembly using a variable area bypass injector. 
   
   
     16. A gas turbine engine assembly in accordance with  claim 14  wherein said at least one core engine bypass duct comprises an inner bypass duct positioned radially outward from said core gas turbine engine and an outer bypass duct positioned radially outward from said inner bypass duct, each of said plurality of fairings in flow communication with said inner bypass duct, each of said plurality of strut members in flow communication with said outer bypass duct. 
   
   
     17. A gas turbine engine assembly in accordance with  claim 14  wherein each of said plurality of fairings and said plurality of strut members in flow communication with said nozzle bypass duct. 
   
   
     18. A gas turbine engine assembly in accordance with  claim 14  wherein each of said plurality of fairings comprises a valve that facilitates controlling an amount of airflow channeled toward said plurality of strut members. 
   
   
     19. A gas turbine engine assembly in accordance with  claim 14  wherein the portion of the airflow channeled from each of said plurality of fairings to said plurality of strut members is channeled along an outer surface of said plurality of strut members to facilitate film cooling said outer surface of said plurality of strut members. 
   
   
     20. A gas turbine engine assembly in accordance with  claim 14  further comprising a valve positioned between each of said plurality of fairings and said plurality of strut members, said valve facilitates combining an amount of the airflow channeled from each of said plurality of fairings with the airflow discharged from said core engine.